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1.
Antibiotics (Basel) ; 12(11)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37998803

RESUMO

Currently, biofilm-forming bacteria are difficult to treat by conventional antibiotic therapy and are, thus, becoming a clinical and epidemiological problem worldwide. Medicinal plants have been identified as novel alternative treatments due to their therapeutic and antimicrobial effects. In this context, the present study aimed to determine the total phenolic content, antioxidant capacity, and antimicrobial and anti-biofilm potential of nine extracts of Hymenaea courbaril (Fabaceae), popularly known as Jatobá. Furthermore, extracts that exhibited biofilm inhibitory activity against S. aureus (ATCC 25923) were selected for UPLC-HRMS/MS chemical analysis. Our results showed a high total phenolic content, mainly in the stem bark extract, and that the plant is rich in compounds with antioxidant activity. In the anti-biofilm analysis, leaf extracts stood out in comparison with chloramphenicol, with inhibition percentages of 78.29% and 78.85%, respectively. Through chemical analysis by UPLC-HRMS/MS, chrysoeriol-7-O-neohesperidoside, isorhamnetin-3-O-glucoside, and 3,7-di-O-methylquercetin were annotated for the first time in the leaves of H. courbaril. Therefore, these results showed the potential use of H. courbaril as an antioxidant and point to its use in antimicrobial therapy with an anti-biofilm effect.

2.
Curr Pharm Biotechnol ; 20(5): 433-444, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30963968

RESUMO

BACKGROUND: Currently, the treatment of infectious diseases has not always been successful due to the emergence of microbial resistance worldwide. OBJECTIVES: This study aimed to evaluate the antioxidant activity, content of total phenolic compounds and flavonoids, antifungal potential and antibacterial action of six medicinal plants found in the Cerrado, leaf extracts of Boldo (Peumus boldus), Goiaba (Psidium guajava), Assa-Peixe (Vernonia polysphaera), Abacate (Persea americana), Eucalipto (Eucalyptus citriodora) and raw sap of Bálsamo (Jatropha multifida). METHODS: The antioxidant activity was also determined through the DPPH, ABTS and phosphomolybdenum assays. In addition, the total phenolic content and flavonoid dosage were analyzed using the Folin- Ciocalteu method and the aluminum chloride test, respectively. RESULTS: All extracts, except from Assa-Peixe, showed promising values against Staphylococcus aureus, with halos varying from 13-20 mm. Analysis of the minimum inhibitory concentration (MIC) values of the six medicinal plants revealed inhibitory activity of S. aureus, with concentrations varying from 3.12-12.5 mg/mL, which is a significant result considering that S. aureus is one of the main causes of hospital infections. CONCLUSION: In the analysis of the phytochemical profile, Goiaba contained the best yield of phenolic compounds and total flavonoids, as well as higher antioxidant activity by DPPH and phosphomolybdenum, demonstrating that this species contains antioxidant components that can sequester free radicals under in vitro conditions. Therefore, the crude extracts investigated are promising and their antibacterial and antioxidant actions should be thoroughly studied.


Assuntos
Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Flavonoides/isolamento & purificação , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Plantas Medicinais/química , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Compostos de Bifenilo/química , Brasil , Etnofarmacologia , Flavonoides/farmacologia , Testes de Sensibilidade Microbiana , Fenóis/farmacologia , Picratos/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Staphylococcus aureus/efeitos dos fármacos
3.
Mem Inst Oswaldo Cruz ; 106(3): 316-21, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21655819

RESUMO

Human rhinoviruses (HRV) are usually associated with mild respiratory symptoms in children. However, some studies have found that HRV can cause severe disease, especially when the patient is co-infected with a second virus. In this study, 532 nasopharyngeal aspirates (NPAs) were collected over a nine-year period from children at the Clinics Hospital of Uberlândia. The collected NPAs were then tested for HRV RNA using the reverse transcription-polymerase chain reaction. Eighty-three specimens from children diagnosed with lower respiratory tract illness (LRTI) were positive for HRV RNA and were then tested for the presence of eight other respiratory viruses. A second virus was detected in 37.3% (31/83) of the samples. The most frequent clinical diagnosis was bronchiolitis, followed by other LRTI and then pneumonia. The frequency of severe disease in children infected with more than one virus was not significantly different from the frequency of severe disease in children infected with HRV alone. Children infected with both HRV and parainfluenza virus (1.5 m.o.) were significantly younger than those infected by HRV alone (5.0 m.o.) (p = 0.0454). Overall, these results suggest that infection with a second virus does not lead to a higher frequency of severe syndromes in children presenting with LRTI.


Assuntos
Nasofaringe/virologia , RNA Viral/análise , Infecções Respiratórias/virologia , Rhinovirus/isolamento & purificação , Adenoviridae/genética , Adenoviridae/isolamento & purificação , Criança , Humanos , Vírus de RNA/genética , Vírus de RNA/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rhinovirus/genética , Estações do Ano , Índice de Gravidade de Doença
4.
Mem. Inst. Oswaldo Cruz ; 106(3): 316-321, May 2011. ilus
Artigo em Inglês | LILACS | ID: lil-589040

RESUMO

Human rhinoviruses (HRV) are usually associated with mild respiratory symptoms in children. However, some studies have found that HRV can cause severe disease, especially when the patient is co-infected with a second virus. In this study, 532 nasopharyngeal aspirates (NPAs) were collected over a nine-year period from children at the Clinics Hospital of Uberlândia. The collected NPAs were then tested for HRV RNA using the reverse transcription-polymerase chain reaction. Eighty-three specimens from children diagnosed with lower respiratory tract illness (LRTI) were positive for HRV RNA and were then tested for the presence of eight other respiratory viruses. A second virus was detected in 37.3 percent (31/83) of the samples. The most frequent clinical diagnosis was bronchiolitis, followed by other LRTI and then pneumonia. The frequency of severe disease in children infected with more than one virus was not significantly different from the frequency of severe disease in children infected with HRV alone. Children infected with both HRV and parainfluenza virus (1.5 m.o.) were significantly younger than those infected by HRV alone (5.0 m.o.) (p = 0.0454). Overall, these results suggest that infection with a second virus does not lead to a higher frequency of severe syndromes in children presenting with LRTI.


Assuntos
Criança , Humanos , Nasofaringe , RNA Viral , Infecções Respiratórias , Rhinovirus , Adenoviridae , Adenoviridae , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vírus de RNA , Vírus de RNA , Rhinovirus , Estações do Ano , Índice de Gravidade de Doença
5.
Mem Inst Oswaldo Cruz ; 105(5): 712-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20835622

RESUMO

Human adenoviruses (HAdV) are a major cause of acute respiratory diseases (ARD), gastroenteritis, conjunctivitis and urinary infections. Between November 2000-April 2007, a total of 468 nasopharyngeal aspirate samples were collected from children with ARD at the Clinics Hospital of Uberlândia. These samples were tested by immunofluorescence assay (IFA) and 3% (14/468) tested positive for the presence of HAdV. By performing polymerase chain reaction (PCR) to detect HAdV DNA in samples that tested negative or inconclusive for all viruses identifiable by IFA (respiratory syncytial virus, parainfluenza viruses 1, 2 and 3, influenza viruses A and B and HAdV), as well as negative for rhinoviruses by reverse transcription-PCR, additional 19 cases were detected, for a total of 33 (7.1%) HAdV-positive samples. Nucleotide sequences of 13 HAdV samples were analyzed, revealing that they belonged to species B, C and E. Further analyses showed that species C (HAdV-2) was the most prevalent among the sequenced samples. To our knowledge, this is the first report describing the presence of HAdV-4 in Brazil. We also detected an isolate that was 100% identical to a part of the feline adenovirus hexon gene sequence.


Assuntos
Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/genética , DNA Viral/genética , Nasofaringe/virologia , Infecções Respiratórias/virologia , Adenovírus Humanos/isolamento & purificação , Animais , Sequência de Bases , Brasil , Gatos , Pré-Escolar , Humanos , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Infecções Respiratórias/diagnóstico , Estações do Ano
6.
Mem. Inst. Oswaldo Cruz ; 105(5): 712-716, Aug. 2010. ilus
Artigo em Inglês | LILACS | ID: lil-557235

RESUMO

Human adenoviruses (HAdV) are a major cause of acute respiratory diseases (ARD), gastroenteritis, conjunctivitis and urinary infections. Between November 2000-April 2007, a total of 468 nasopharyngeal aspirate samples were collected from children with ARD at the Clinics Hospital of Uberlândia. These samples were tested by immunofluorescence assay (IFA) and 3 percent (14/468) tested positive for the presence of HAdV. By performing polymerase chain reaction (PCR) to detect HAdV DNA in samples that tested negative or inconclusive for all viruses identifiable by IFA (respiratory syncytial virus, parainfluenza viruses 1, 2 and 3, influenza viruses A and B and HAdV), as well as negative for rhinoviruses by reverse transcription-PCR, additional 19 cases were detected, for a total of 33 (7.1 percent) HAdV-positive samples. Nucleotide sequences of 13 HAdV samples were analyzed, revealing that they belonged to species B, C and E. Further analyses showed that species C (HAdV-2) was the most prevalent among the sequenced samples. To our knowledge, this is the first report describing the presence of HAdV-4 in Brazil. We also detected an isolate that was 100 percent identical to a part of the feline adenovirus hexon gene sequence.


Assuntos
Animais , Gatos , Pré-Escolar , Humanos , Infecções por Adenovirus Humanos , Adenovírus Humanos , DNA Viral , Nasofaringe , Infecções Respiratórias , Adenovírus Humanos , Sequência de Bases , Brasil , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Infecções Respiratórias , Estações do Ano
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